Many of these patterns are available as frameworks and you do not need to implement them from scratch. As a side effect, the frameworks, such as O/R mapping and web presentation tools, have a tendency to hide their implementation techniques. The patterns cataloged and described by Martin Fowler will help you understand what happens behind the scene and and use this knowledge for optimizing, troubleshooting, and improving the design of your applications.

This book has something valuable for everybody. If you are new to the industry, you will learn about common recurring problems building enterprise applications and study techniques to solve them. If you used these patterns before, you will deepen your understanding of them.